3 ms·That's a ... really really large greenhouse. They're about halfway to a workable Mars habitat.by droithomme 7y agoThat's a ... really really large greenhouse. They're about halfway to a workable Mars habitat.aidos 7y agoNot as far as greenhouses go!d33 7y agoIf building two such big greenhouses was enough to live on Mars, we'd already have been there.